package com.state.machine.configuration;

import com.state.machine.constants.Events;
import com.state.machine.constants.States;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.statemachine.config.EnableStateMachine;
import org.springframework.statemachine.config.EnumStateMachineConfigurerAdapter;
import org.springframework.statemachine.config.builders.StateMachineConfigurationConfigurer;
import org.springframework.statemachine.config.builders.StateMachineStateConfigurer;
import org.springframework.statemachine.config.builders.StateMachineTransitionConfigurer;
import org.springframework.statemachine.listener.StateMachineListener;
import org.springframework.statemachine.listener.StateMachineListenerAdapter;
import org.springframework.statemachine.transition.Transition;

import java.util.EnumSet;

@Configuration
@EnableStateMachine
public class StateMachineConfig extends EnumStateMachineConfigurerAdapter<States, Events> {
    private Logger logger = LoggerFactory.getLogger(getClass());

    @Override
    public void configure(StateMachineStateConfigurer<States, Events> states) throws Exception {
        // 定义状态机中的状态
        states.withStates().initial(States.UNPAID).states(EnumSet.allOf(States.class));
    }

    public void configure(StateMachineTransitionConfigurer<States, Events> transitions) throws Exception {
        transitions.withExternal()
                .source(States.UNPAID).target(States.WAITING_FOR_RECEIVE) // 指定状态来源和目标
                .event(Events.PAY) // 指定触发事件
                .and()
                .withExternal()
                .source(States.WAITING_FOR_RECEIVE).target(States.DONE).event(Events.RECEIVE);
    }

    public void configure(StateMachineConfigurationConfigurer<States, Events> config) throws Exception {
        // 指定状态机的处理监听器
        config.withConfiguration().listener(listener());
    }

    @Bean
    public StateMachineListener<States, Events>  listener() {
        return new StateMachineListenerAdapter<States, Events>(){
            @Override
            public void transition(Transition<States, Events> transition) {
                if (transition.getTarget().getId() == States.UNPAID) {
                    logger.info("订单创建，待支付");
                    return;
                }
                if (transition.getSource().getId() == States.UNPAID && transition.getTarget().getId() == States.WAITING_FOR_RECEIVE) {
                    logger.info("用户支付完成，待收货");
                    return;
                }
                if (transition.getSource().getId() == States.WAITING_FOR_RECEIVE && transition.getTarget().getId() == States.DONE) {
                    logger.info("用户已收货，订单完成");
                    return;
                }

            }
        };
    }
}
